Introduction: The CoQun® study is a multicenter, controlled trial aimed to evaluate the neuroprotective effects of Coqun®, an ophthalmic solution of Coenzyme q10 (CoQ10) and Vitamin E (VitE), in patients affected by primary open-angle glaucoma (POAG). Pre-clinical studies and small non-controlled clinical trials have previously shown a potential role of CoQ10 and VitE in glaucoma neuroprotection, both in vitro and in vivo. Methods: Randomized, parallel arm, multicenter, double-blind study. POAG patients with an IOP ranging from 17 to 21 mm Hg on monotherapy with a prostaglandin analogue (PGA) will be considered for study enrollment. Inclusion criteria will be visual field (VF) mean deviation between − 4 and − 10 dB and VF Pattern Standard Deviation between 4 and 10 dB. Eligible patients will be randomized to receive CoQun® (Arm A) or placebo (Arm B), in addition to PGA monotherapy. Planned Outcomes: Primary outcome will be time to progression, defined as the time between the baseline visit and the visit with confirmed VF progression. A total of 612 patients are planned to be enrolled, to detect a hazard ratio of 0.65, with a power of 80% and an alpha error of 0.05 (two-sided). For study power calculation, 10% non-evaluable patients are assumed. This is the first study investigating, in a randomized, double-blind and controlled fashion, the neuroprotective effects of CoQ10 and VitE in POAG patients. Trial Registration: ClinicalTrials.gov identifier, NCT03611530.
